DE2559006C2 - Message transmission systems, in particular telephone and data switching systems - Google Patents

Description

a) one combined with the analog / digital conversion Voice seizure detection (22.U, Fig. 11),

b) a first buffer store (24), the groups of Connections (20) for temporary digital intermediate storage of the connections assigned to these connections Traffic is assigned (Fig. 4, Fig. 6),

c) a second buffer store (28), the at least one long-distance connecting line (VFL) for the temporary intermediate storage of the time-concentrated traffic volume assigned to the main line assigned in digital form; «{, where between the first buffer memory (24) and the second buffer memory (28) a switching stage (26, Fig. 7) for optional switching through a connection between the memory locations of the first Buffer memory and the storage locations of the second buffer memory is switched on (Fig. 4, Fig. 6),

d) a central controller (34, 36) for controlling the network control unit and in particular for detecting the voice seizure signals and for generating a compression mask with one bit per channel, which is also transmitted in a specific, real channel (EK1) of a frame (Fig . 4),

e) a section allocation memory (AZS) in the switching stage (26), with a memory part (26.1.2, FIG. 7) for storing the compression mask, and

f) a voice compression compression circuit (30) for dividing the voice-occupied virtual channels consecutively to the real channels (Fig. 10, 13).

2. Device according to claim 1, characterized in that the voice assignment compression circuit (Fig. 13) with the output of the second buffer memory (28) for the activity compression of the departing « the traffic of a large number of virtual channels, the discrete storage locations with several blocks in the second buffer memory (28) are assigned, into a smaller number of blocked real-time multiplex channels is connected by the suppression of currently inactive virtual telephony channels, and that further the first Buffer memory an activity detector circuit (22.1.3.1) for determining and monitoring the of assigned to the connections (20) after the first buffer memory (24) current traffic for voice activity is.

3. Device according to claim 2, characterized in that the storage capacity of the second buffer memory (28) is at least one order of magnitude greater than the storage capacity of the first buffer memory (24) and that the storage of the first Buffer memory outgoing traffic in the second buffer memory takes place accordingly in blocks, with the respective activity bits are assigned block by block to the traffic stored in blocks in the second buffer memory.

4. Device according to claim 2, characterized in that a blocking circuit (Fig. 13) is provided is through which a selective blocking of active virtual channels with traffic intended for trunk lines can then be carried out if the number is active virtual channels exceeds the capacity of the smaller number of available real channels and that the transmission of the selection serving circuit (22.13.1) in cooperation with the blocking circuit during transmission, the selection of the suppressed virtual channels for a display of the blocked active, virtual channels are also used.

Heretofore, communications satellites have been used for point-to-point communications, typically between highly concentrated sections of Bearer telephone lines and communications systems or television broadcast networks. At a A connection running via communications satellites usually takes place signal transmission between earth stations and possibly a certain time concentration and time division multiplex transmission between different subscriber stations and the individual nodes equipped with radio stations. The connections of the individual subscriber circuits at the exchanges were generally the public and / or left to private transmission line owners.

Because of the very high capital expenditure involved in the construction and circulation of a communications satellite, it has hitherto been customary to install earth stations only where there was already a high concentration of traffic. However, this increases the marketability of such a system and the risk of investing capital considerably. In addition, this unnecessarily creates an additional traffic load for small ones private networks (for example a leased line network for telephone and data traffic in a private organization), which are served much more effectively if they had immediate access to communications via satellites and other transmission lines.

For the state of the art with regard to a communication system of the above type, reference is made to DE-OS 22 14 S63 pointed out.

The present invention is therefore intended to establish a modular connection setup based on speech interpolation Switching systems with an incremental allocation of satellite channels and trunk channels lesser Create capacity on small, private telephone and data user networks, so that large and massive transmission capacities can be effectively carried out in small sections

are available, can be expanded in small sections and, for many users connected to small networks, balanced access to them Allow high-performance, high-quality cables. Another aspect of the present invention is to see that the transmission capacity in a transmission system of trunk lines can be allocated in such a way that time division multiplexed and Raummultiplexkanäie are provided, with an upper a communication satellite leading connection is widely accessible as the main transmission route.

The solution according to the invention is characterized in claim 1.

An advantage of the present invention is that it enables remote connection establishment between many Access points that are accessible to private telephony and data transmission users and many up Measures time-concentrated virtual channels can be produced, so that by the time concentration of the virtual channels handling the overhead costs both for the connection, and for the traffic Long-distance transmission can be reduced and the choice of location for earth radio controls is facilitated.

Another advantage of the invention is that any local connections between the individual connection points for telephone subscriber or telephone private branch exchanges without going through public exchanges (i.e. if such a type of use is economically preferable) or that a through-connection of long-distance connections to other exchanges via land lines is made possible if the exchange in question is fully occupied.

Another advantage of the invention is that the possible connections within a network several exchanges, which are connected to the transmission channels, for a more efficient use the connecting lines and part of the capacity of the main transmission path that leads via the satellite, can be summarized.

There is another important advantage of the invention in that the concentration of the traffic on the virtual channels is less than the concentration of the over the Traffic carried by satellites, so that the traffic coming from several switching modules is gradual and selectively in a highly concentrated manner and transmitted according to the time division multiplex method with the formation of highly effective structured traffic bundles after the satellite can be.

Furthermore, the invention is characterized in that the traffic between the virtual channels and the corresponding real channels of the corresponding trunk lines can be subjected to activity compression in that larger groups of virtual Channels previously assigned groups of real channels, so that the activity at the connection points accessible to the individual telephone user is monitored determined telephone activity of the connection point to a more concentrated block activity in connection-wise grouped virtual channels in each period of time Long-distance transmission summarizes, selectively suppresses the long-distance transmission of such virtual channels in each Trunk line frames are assigned to a currently inactive telephone connection line and the active traffic thus determined is compressed by only the actually existing consumption of non-suppressed virtual channels in successive channels or Periods of the pipeline connections and equal

10

15th

20th

25th

30th transfers tax and control information in good time, which supplies information to the corresponding exchange about which virtual channels are suppressed and which are soft are not suppressed, and by using the information transmitted in this way for a correspondingly expanded distribution of the traffic thus transmitted to the corresponding destination connection points via the corresponding vir ^ transmits current channels and the corresponding dial-up connections.

The invention will now be described on the basis of exemplary embodiments in conjunction with the accompanying drawings described in more detail. The features of the invention to be protected are also attached Patent claims contained in detail. In the drawings shows 1 schematically shows the organization of a communication network according to the invention,

2 shows a block diagram for the digital connection and time concentration according to the time division multiplex method for a node of a radio station according to Fig. 1,

FIG. 3 shows the modular assembly 10 of the circuit shown in FIG. 2 for step-by-step switching, temporal Underconcentration and time division multiplexing.

FIG. 4 shows a block diagram to illustrate a capacity expansion of the block diagram shown in FIG. 3. 5 A and B equivalent circuits for long distance and local exchange connections, as implemented in the section allocation memory 26 of the circuit block 10,

Fig. 6 shows the organization of the local line and trunk buffer module in Fig. 3 in relation to the Section allocation memory 26 and the corresponding modular groups of 96 leads and 96 virtual transmission channels,

7 shows the organization of the section allocation memory and the associated address control for Switching through communication links with up to four subsets of 96 connection lines each and 96 virtual trunk lines for any connection between each connection line in the groups of connecting lines and the trunk buffer space corresponding to each virtual channel into the corresponding groups,

8 shows the format of the real channels and the frames for time-concentrated trunk lines;

FIG. 9 shows the processing of a call through circuit in relation to the system of FIG. 7 and the effect of tabular circuit restrictions;

Fig. 10 shows a logic circuit for speech activity compression or speech inflection compression in relation to it aui Aie 7 ** 1 «lines,

11 shows the processing of the voice seizure recognition in connection parts connected via trunk lines Circuits and the processing of the corresponding activity bits for voice occupancy compression for the corresponding assigned virtual channels of the trunk lines,

Fig. 12 shows the bit / byte format of the voice occupancy compression mask, which is shown in a predetermined range in each multiplex frame on a remote transmission line to distinguish the assignment-compressed assignment of other channels <hs of the same frame with respect to serves original virtual channels,

13 shows a logic circuit for channel suppression in the event of overload in a number of virtual channels during a trunk line frame, the capacitance

did on real channels for the corresponding pipeline in this framework is exceeded,

14 to 16 show the signal formats of the pulse frames and bursts which are required for transmission from the earth radio station after the satellite are used and s

17 shows a block diagram for the connection of the network management circuit which is used for collecting Information from sub-networks and when redefining the ones to be complied with when switching through Limits are used.

Fig. 1 shows a private or partially private communication network, that is constructed according to the invention. Three sub-networks 12 and 3 are for one after Telecommunication link operating on the time division multiplex principle via a geo-stationary satellite 4 IS connected with each other. Although only three sub-networks are shown here, of course, essential more sub-networks are used.

The sub-networks communicate with one another via time-synchronized message or information bundles that contain, to a large extent, time-concentrated information in digital form that is modulated onto the identical carrier frequencies. The timing of the individual information bundles of the individual sub-networks is selected so that the information bundles are transmitted interleaved after the satellite in such a way that they do not overlap on the satellite. The satellite converts the carrier frequency of each information bundle to a predetermined frequency in a different frequency band. maintains the information modulation and transmits this information to all sub-networks in parallel at the same time. This information transmitted to the subnetworks is then broken down again into its individual channels, deconcentrated, divided up according to the cycle and distributed to the individual destination connection lines. The transmission paths between the sub-networks 1 to 3 and the satellite 4 are denoted by 4.1, 4.2 and 43.

The sub-networks 1 to 3 provide the switching or switching, the time concentration, the conversion according to the time division multiplex method and the modulation. The individual modules can be geographically distant from one another or they can be close to one another. The information processed within the subnetworks and between the subnetworks is always digital, but can be received and also output by the subnetworks in analog form. The corresponding sub-networks 1 to 3 can thus operate analog telephone sets 1.1.1, 2.1.1, 3.1.1 via corresponding subordinate exchanges 1.1., 2.1 and 3.1, respectively. The sub-networks can also connect to data processing machines via data terminals, as indicated schematically at 1Λ, 22, and 3.2, the data being sent and received in modulated form. The sub-networks can also be connected to data processing systems, which are shown at 13, 23 and 33 , the data transmission taking place here in the baseband, ie in unmodulated form.

Assume that the sub-networks - for example 1 and 2 can come into contact with one another via a dedicated line or leased line 5.

The information is with full concentration between the sub-networks and the satellite at one transmission speed of approximately 49.4 megabits per second while at the subconcentration nodes within each sub-network the information about spatially separated trunk lines the time division multiplex with a transmission speed of 1.54 megabits per second (a transmission speed that corresponds to the signal capacity of the telephone transmission lines from the Type Tl is compatible).

The carrier frequencies for satellite transmission represent only a small part of the total transmission capacity of the satellite represents which part through the subnetworks to form a private or independent allocable network is used.

Fig. 2 shows the basic organization of a sub-network. The information arrives at the sub-network in deconcentrated form via connecting lines to a network control unit 10 and leaves it in the same way. These modularly arranged network control units 10 are used to switch through local calls and long-distance calls as well as time concentration and time division multiplexing with respect to the long- distance lines 5, 5.1 and 10.1 and serve as connecting line sections in long-distance connections. All of the information is processed entirely in digital form within a network control unit and the trunk lines 5, 5.1 and 10.1 connected to it. In the connection lines provided for external users, the information arriving in unfocused form can be in analog or digital form. For the trunk line transmission section, which leads via the satellite, the concentrated information, as it is supplied by the network control units 10 , is concentrated again and concentrated in the network access unit 12 according to the time division multiplex method to a transmission speed of 49.4 megabits per second, at the Earth radio station 14 modulated onto the corresponding carrier frequency and emitted via antenna 16 to satellite 4. In the opposite direction, the received information is demodulated, broken down into the individual channels, expanded and distributed to the individual connection connections of the network control unit 10 .

FIG. 3 shows a typical network control unit 10 , with the aid of which the switching through, the time concentration and the processing can be carried out according to the time division multiplex principle. The information arrives at the connection points 20 in a deconcentrated form. The telephone (voice) information is transmitted in analog form to a sub- exchange 1.1 and converted from the analog form into a delta-modulated digital form in the analog-to-digital converter 22 , which can be available to several connecting lines. The delta-modulated telephone information and other data recorded in digital form are stored in the buffer memory 24 for the individual connection lines and bit-serially for them, this buffer memory 24 preferably being designed as an access-free memory. The buffer memory 24 contains separate memory units for each traffic direction with respect to the connection lines. The traffic arriving at the connection points 20 is stored in the input buffer memory 24.1.1 and the traffic delivered at the connection points 20 is taken from the output buffer memories 24.1.2.

The line buffer memories 24 enter into an information exchange with an optional section allocation memory 26, which can also be referred to as a switching memory, the transmission taking place in parallel within the bits for each transmission line and in series for the bytes. The section allocation memory 26 effects a byte-wise transmission between different connection points 20 of the same network control unit (local connection) and / or between connecting lines

7 8

lines and trunk buffers 28 (remote connection. In a predetermined channel of each

fertilize). A mask is then transmitted from an input buffer memory 24.1.1 grain frame, which the

Mending long-distance traffic is displayed in virtual channels after a long-distance line has been selected. There

transfer memory 28.1.1 and from a telecommunications network this mask for each virtual channel block only

input memory 28.1.2 incoming traffic will contain 5 two bits (one bit and an additional redundancy

transferred to a connecting line memory 24.1.2. bit for forward error correction) becomes the ratio of

Fernvertshr between trunk line buffers 28 information bits for mask bit advantageously very and corresponding trunk lines 10.1 (or 5 or 5.1, high. The details of the voice occupancy compression see FIG. 2) will be described byte by byte with reference to the.
Section allocation memory 26 and one after the other in blocks to A common control microprocessor 34 is available to all other (in blocks of 24 bytes) in relation to the corresponding time-division multiplex channels of the connection lines available to the exchange and supplies the corresponding coordinated Transfer time control 10.1 or long-distance lines (10.1 or 5.1 or 5). tion, the setting of the tables (in particular in the interim, the connection memory of Fig. 7 coming from the section allocation memory 26) and thus establishes the traffic running on a trunk channel and yeasts the transmission of the monitoring radio corresponding outgoing trunk line buffer memory with respect to the other network control units 10 28.1.1 and stored as an entire block to the remote network (via predetermined channels of the trunk line. From the incoming trunk lines). In connection with the call processing buffer memory 28.1.2 at the section allocation units 36 (one traffic each for each group of connection line memory 26 is stored in a memory), the shared processor 34 provides space in a 24 byte wide block byte by byte to the from the dialing information selectively outputs connections between memory 26. At the remote end of the trunk lines, connecting lines and storage locations in the section, the information can either be obtained in deconcentrated allocation memory 26.

Form to be delivered to the connecting lines or 25 The method for switching through a connection but in the form of segments in a more concentrated form and operates under boundary conditions that apply to all network-wide control units 10 of the private network form specified above using the time-division multiplex method be delivered to the satellite. The block storage units can be changed in a coordinated manner, so that each network location in the memory 28.1.1 are here as a virtual control unit 10 is able to determine whether all Fernleif; ngskanalkanals designated. 30 preferably designated segments of a remote connection

The number of these virtual channels is about twice as ses, for example over the module 10, the remote connection large like the number of real channels actually in training lines 10.1, the module 12 and the satellite 4 each frame of the corresponding transmission line 10.1 (or are ready for use before an exchange of monitoring 5 or 5.1) is available. So that all active communication control information is carried out, with their virtual channels in the corresponding real channels 35 help it is determined whether in each section of this liaison accommodation can, selected virtual channels in turn a free channel is available to the connector outgoing trunk line to be fully established during the transmission. Because these limit values changed and then such suppressed ones are viral, each unit 10 or 12 of the total Channels are reinserted by being logically isolated at the th system of the network when arriving Transmission from the trunk lines a 40 for example for repairs or other purposes without inserts white noise. The suppression and thus the operation of the entire network temporarily The production of these channels will have to be set by voice occupancy.

Compression circuits 30 performed. The modular structure of the station 10 allows a switching method is related to the language of speech or data transmission known as TASI and a concentration interpolation method, such as that used in remote transmission in relatively small assemblies, such as in the transmission long distances are used. The sub- Figs. 4 and 6 are shown. Equivalent trunk line and differential is that the activity in the various local trunk circuits within the network control telephone transmission lines represented by the unit 10 are illustrated in FIGS. 5A and 5B.
Buffer memory 28 is shown; Line buffer memory buffer memory 28, corresponding to the through-connection connection 24 and trunk line buffer memory 28, fertilize, as it is in the section allocation memory 26, FIG. 5A shows that the section allocation memory 26 has been carried out, is allocated. Another difference between each connection line is that the activity of the individual 55 can be generated, for example each of the modules 24.1. 24.2 connecting lines at the telephone connections for each etc. is assigned and each virtual channel, which any byte are specially determined, while at the one of several trunk line buffers 28.1. 28.2 Junction points for the trunk lines the activity is assigned to. 5B shows that each connection line is represented with one bit in an entire block, ie a virtual channel through the direction of the various modules shown in FIG. This results in a substantial profit in the ratio of productive, ie can.

bits representing traffic to which only operational The operation of the section allocation memory 26

purpose serving activity bits in the switch. This can best be seen from an explanation of FIGS. 6 and 7

Understand the individual virtual channels for outgoing telephone. Fig. 6 shows that the section allocation memory

traffic in the buffer memory 28.1.1 assigned activity 65 rather contains 26,768 byte storage locations, which by the over

labels thus determine which virtual channels can be allocated to an input

each frame are addressable for a block multiplex transmission fiber. This figure also shows that the

the corresponding trunk line 10.1 (or 5 or 5.1) sub-input buffers and the output buffers

are arranged in pairs as A / B memories. For example, one memory is being loaded while the other memory is being stored. Thus, each input buffer memory or output buffer memory contains a module with two 96-byte sections A and B. which alternately receive information from 96 corresponding connecting lines and deliver it to 96 corresponding byte memory locations in the section allocation memory 26. However, this means that the line buffer operation and the exchange of transmission sections can take place at the same time.

In the same way, each outgoing trunk line buffer memory 28.1.1 (up to 4) contains 96 block sections A and B, which are to be understood as virtual channels, which alternately receive information from the section allocation memory and at the same time previously received information to the corresponding trunk lines 10.1 (or 5 or 5.1 ) hand over. The input trunk line buffer stores 28.1 and 2- in the storage sections A and B each contain only 46 blocks. The process of buffering the trunk lines and exchanging time segments can thus run simultaneously and it can be seen that up to 4 times 96 connection lines can be effectively connected and assigned via remote connections with up to 4 times 96 virtual channels or 4 times 96 local dial-up connections via the segment allocation memory 26.

7 shows the modular organization of the section allocation memory 26. The section allocation memory AZS consists of 768 (8 x 96) addressable byte storage locations 26.1.1 for storing information bytes and 768 correspondingly addressed storage locations 26.1.2 for activity bits. These memory locations can be controlled with random access via a schematically illustrated address register 26.1.3. All memory locations of the AZS are loaded once and saved once during each exchange frame of 1536 (2 x ä 768) memory cycles. The timing of a frame is designed in such a way that an exchange of 4 x 96 bytes between memories 24 and memories 28 can be carried out 24 times in 6 milliseconds (so that the information signal transmission speed of 1.544 megabits per second can be maintained on the transmission channels) . A two-stage counter 26.2.1 controls the alternating reading and writing within the frame cycles. During successive write cycles of AZS is driven by sequential states of the counter 26.2.2, while the AZS in consecutive read cycles that occur between successive write cycles, is driven by an address that the interconnect control memory modules derived from a (up to 4) and an address is in the ZVS , which is determined by the count in the counter 26.2.2 .

In the first half of each frame, that is, during the first 768 cycles, one half (e.g. the upper half) of the memory locations in the section allocation memory 26 is successively loaded from the corresponding memory locations from the input line buffers 24.1.1 , while the memory locations are simultaneously loaded the lower half in any order either after corresponding byte storage locations of successive block storage locations for virtual channels in the outgoing trunk line buffer 28.1.1 or in successive byte storage locations of outgoing line buffer memory 24.1.2 and stored there. In the remaining half of the frame, the other (lower) half of all section memory locations of the section allocation memory is loaded one after the other from the input trunk line memory 28.1.2, while the memory content of the first half in any order after successive memory locations either from the outgoing buffer memory 28.1.1 for virtual Channels (in corresponding byte order positions) or to the outgoing line buffer memory 24.1.2 and stored there.

While the section allocation memory 26 (for example, by 24.1.1) loaded, loads the corresponding one of the lead activity bits simultaneously in the memory 26.1.2. During the storage process, the activity bits are transmitted and converted into activity bits for the virtual channels. (An active "one" bit, which relates to the transmission of any byte relating to a virtual channel allocated to telephony traffic, and carried over a cycle frame with slice allocation, calls an active "one" bit for the entire, in that frame stored block of a virtual channel).

The output signals of the interconnection control memory are all fed together to a selection circuit 26.23 which alternately selects either the counter 26.2.2 or the output signal of the interconnection control memory and thus addresses the section allocation memory 26 in successive write and read cycles of the corresponding frame.
When establishing a remote connection (telephony or data), the common control circuits 34 and 36 first determine whether all sections or sections of the network that are assigned to a main connection or an alternative connection in a manner that can be restricted to establish this connection are also ready for operation (i.e. for the establishment of the desired Connection are available) and, if so, whether suitable, unoccupied virtual channels are available for each section or each segment. If this is the case, the connection is set up by making appropriate entries in the interconnection control memory in the network control unit 10 , whereby the conversion address is identified which is required for the conversion from the time segment of the connection line to the time segment of the virtual channel in the segment allocation memory 26 . Corresponding entries in the network access unit 12 designate the allocation of the virtual channel and its conversion into a channel with an information bundle for transmission to the satellite.

Since the boundary conditions for each sub-section of the network (main and alternative routes) for long-distance connections are contained in the tables in the processors 34 of the network control unit 10 , the network can either be designed in different ways for the separation of parts during a repair and / or in can be expanded in an orderly manner by further modules or network control units 10 .

Fi g. 8 shows the format of a frame for a feeder trunk line 10.1 (5 or 5.1). Each frame is 6 milliseconds long and contains 48 real channels EKO to EKXl. With the exception of the EKO and EKi channels, all channels contain 192 information bit time segments that can be assigned to a virtual channel. The real channel EKO contains 192 information bit time segments which are allocated for monitoring signaling between the processor 34 and a corresponding station connected at the other end of the trunk line. The incoming long-distance traffic in the EKO channel goes directly to the processor 34 and the outgoing long-distance traffic

■; li 12

'. in channel EKO originates in processor 34 and is associated with a trunk connection

If it comes directly to the long-distance line, bypassing the connecting line, the immediate course of activity becomes.

) uk: buffer memory 28. The EKl channel is the SBK mask as it is in the analog / digital converter 22.1.1 with regard to this

S assigned, which will be discussed in detail. Connection line has been determined as a sample. with

' will. S of the cumulative shares determined in both directions

■; ■ Each channel contains 192 information-bit time segments compared to the same connection line, which are in'ent-

'■ i; as well as a byte coordinate of the buffer memory 24.1.1 intended for the synchronization

fl cut. Change EiCO to EK39 in the first 40 channels and 24.1.2 is saved. This comparison differs

* 'jj the synchronization bits continuously with each other from between the original activity, echo activity and

'j see 1 and 0. In the last eight channels, the io form noise (inactivity), i. H. Pauses in the conversation.

Synchronization bits a very specific pattern (11100100) The activity coordinate in the corresponding time interval

and thus determine the limit of the frame. In cut in the section map will only then

certain (56th) frame, this pattern is loaded with a "one" in the last, if it is an original

eight channel position'.n by another pattern (00011011) before activity or language occupancy acts. A transfer

replaced, and this is used to distinguish the after the 15 generation of 24 bytes with the activity bit "0" over the

Satellite leading main frame. The limits of the corresponding coordinate of the section allocation memory

'■: Main frame are effected by the network access unit chers 26 that the logic circuit for the speech

• 12 as a reference point in time for the order of the corresponding occupancy compression selection 30 the corresponding

■ '' ■ "■ the allocation of the transmission times of information viriucücü channel blocks, ie no ferr. '. Situngskana! EK

bundle used within the frame, as can be seen from a 20 assigns.

I further describe the format for the satellite over- Fig. 10 shows that during the unloading of

¹ result. The real channel 1 contains a voice busy information byte from the section allocation memory

i tion compression mask (SBK mask). This mask 26 for the outbound trunk buffer

. ' limits the possible compression of the following 28.1.1 the corresponding activity bits according to the corresponding

Channels EKl to EKXI in relation to the virtual channels 25 corresponding coordinates of the voice assignment compression

of the memory transfer system 26 and 28. Buffer memory 30.1 are transferred. Subsequent

The channels EKl to EKXt each contain 192 bit time bytes are for virtual channels in the corresponding coordi-

section c, di. in each case a selected virtual data of the outgoing trunk line buffer memory 28.1.1

Are assigned to the channel of the buffer storage system. stored while the corresponding activity bit The memory allocation compression mask (Fig. 12) is overwritten 30 in the buffer memory 30.1. So shows

holds 192 bits (24 bytes), consisting of 12 original Infonna- an activity bit 1, of any byte passed through the

'tion bytes VO to VIl (96 bits) and 12 of the forward error section allocation memory 26 transmitted through

j there are redundancy bytes FO to 511 serving for correction. becomes, an instantaneous activity of the corresponding

The 96 bits from VO to VIl, which are consecutively arranged on the virtual channel. Traffic is always from one

'are accompanied by the 96 virtual 35 activity bits 1 corresponding to the position. The current activity bit

Channels of a corresponding trunk buffer and the previous activity bit are stored in each

geordi.it. The value of each bit (0.1) represents the allocation coordinate of the buffer memory 30.1 (since it represents the activity

status of the corresponding virtual channel (locked status of the corresponding virtual channel in the eye

or switched through). The virtual channels that last the current and previous 6 milliseconds

individual consecutive "one" bits of the mask 40 characterize the frame of the section allocation memory

I are assigned (read from left to right) are nen) during the time T (EKQ) via the AND element 30.3

successively the real channels from EKZ to EKXI to a logical one used to form a new mask

assigned. Transfer circuit 30.2, where the time T iF.KO)

■ Thus, in the outgoing trunk line transmission with the trunk line EKO in the frame together \; starting from the buffer memory 28.1.1, up to 45 menue, in which the corresponding

46 of the 92 memories assigned to the virtual channels are to be allocated to the trunk line in the corresponding trunk line frame. The output of the mask can be assigned to other real channels. In the case of the forming logic circuit 30.2, ie the corresponding incoming long-distance line transmission, the voice seizure compression mask 50 (FIG. 12) generated at the end of the bytes of the voice communication compression mask is transmitted via an interpolation logic which is not shown here and which serves the advance in channel EK1 in a separate voice seizure comment error correction logic stored after ι pressions buffer memory, while the after- an output buffer memory 10.1.1, which acts as an elastic i following channels EKl Ms EKXl in the corresponding memory, transferred so early that the channel long-distance buffer memory 28.1.2 enter (ie the buffer EKl on the long-distance line with the full mask occupied (memory only have 46 memory locations). The coordinates can be 55. These mask bytes of the mask are; ' this buffer memory 28.1 »2 are then also temporarily stored in the buffer memory 30.1 under expansion. -? into the corresponding coordinates of the virtual channels While the new mask is being formed, the ■; i are stored in the section allocation memory 26, monitoring signals from the data processing system, which are indicated by the positions of the "one" bits in the buffered or the processor 34 to the Pipeline duct EKO M mask are marked. This working method will be carried over again. An AND element 30.4 allows this information k to be explained in more detail. after the memory 10.1.1 at such a time that

■ The details of the voice allocation compression are thereby allocated to the real EKO channel.

vj which is best understood from FIGS. 10 and 11. Fig. 11 The from the VK coordinates of the buffer memory 28.1.1

y. shows how the traffic selected to determine the voice occupancy is switched through in the manner according to the outgoing-S activity serving logic circuit 22.13.1 with respect to 65 the buffer memory 10.1.1, so that the

j | f the input line buffers and the output lines EJQ to EKXl of the same trunk line

jt>; management buffer memory «.r 24.1.1 or 24.U and the analog / mens. The selection of the VK coordinates

fe diatal converter 22.1.1 is working. For each of a telephone line, the V bytes last used in the buffer

store 30.1 saved new mask carried out. Each bit of the mask is used to advance an address counter, not shown, and the "one" bits of the new mask are used to delay the incrementation of the counter and the corresponding channel s VK in 28.1.1, as indicated by the counter reading to save. As can be seen from the following description of FIG. 17, the new mask in any case does not contain more than 46 "one" bits and thereby selects those virtual channels through which successive real channels up to the total capacity of real channels 2 to 47 can be occupied.

In the opposite trunk direction from the trunk lines to the section allocation memory 26, the incoming traffic is subjected to renewed timing in the elastic buffer store 10.1.2. The monitoring information arriving in the real channel RKd is masked out by an AND element 30.5 and sent directly to the processor 34. The SBX mask in the real channel EK1 (which has its origin at the distant end of the corresponding long-distance line) is passed through an AND element 30.6 after the SBK buffer memory 30.1 . The traffic arriving in the real channels EKZ to EKXI is selected by an AND element 30.7 and stored in the 46 memory locations of a corresponding incoming trunk line buffer memory 28.1-2 (ie without expansion) and expanded during the next transmission frame for the section allocation memory. During the transfer through the section allocation memory, the retrieval addressing of 28.1.2 is incremented in such a way that it coincides with 46 of the 96 time section coordinates corresponding to the positions of the "one" bits in the recorded mask. The "one" bits of the mask activate an AND element 30.8. which then switch through the stored output signals from the teleiiungspunerspeicher according to the corresponding time segment coordinates of the segment allocation memory. The »zero bits of the mask unlock an AND element 30.9, which switches through an artificially generated noise signal from a noise signal generator 30.10 according to the corresponding coordinates of the virtual channels of the section allocation memory 26 and thus bytes of artificially generated noise into the corresponding coordinates of the outgoing line buffer memory 24. U stores. The generator generating an idling noise synthesizes a noise representing bytes in time division multiplex operation in accordance with the timing of the transmission or exchange frames of the section allocation memory, so that in each section coordinate of a frame serving for transmission from trunk to trunk, the generator emits an audible noise of a low level sends the corresponding coordinates of the outgoing line buffer memory 24.1.1 and the digital / analog converter 22.1Jt to the corresponding output line. This avoids a line in which no voice or information is being transmitted at the moment, giving the corresponding subscriber set the impression of a dead line.

Fig. 13 shows the logic circuit for the generation fio of the SßK mask in relation to outbound transmission on the trunk lines. The activity bits stored in the buffer memory 30.1 of FIG. 10 differentiate the activity status or the voice occupancy status in each virtual channel of the current frame and the previous frame. A further identifier provided for each virtual channel and supplied by the common processor 34 indicates which virtual channels are assigned to a data transmission instead of a telephone transmission. As will become apparent from the following description, data takes precedence over telephone transmission with regard to the allocation of real channels. As can also be seen from the following description, continued activity takes precedence over new telephony activity, and new data activity always takes precedence over telephony activity.

The corresponding activity identifiers of each virtual channel are processed by the logic circuit shown in FIG. D during the time of the channel EKO to form the V bytes of the new mask. An identifier indicating continued data transmission activity is entered by an AND element 50 immediately after an OR element 51 arranged on the output side as a "one" bit in the bit positions of the new mask assigned to the corresponding virtual channels.

Identifies new activity (i.e. an activity in this frame but not in a previous one Frame) are selected by an AND gate 52 and switch the count of a new activity indicating Counter and under the condition of an AND gate 53 as a "one" bit in the new mask that this count does not exceed the value 46. However, if this count exceeds the value 46, then the output of the AND gate 53 is blocked and after a suitable delay the count for new Activity decreased by 1. Although the AND gate 53 is blocked, it is still possible that a "one" bit in the corresponding mask position is formed via a logical channel, which is based on a counter reading for new Data and the AND gates 54 and 55 is formed. The AND gate 54 selects a new data activity indicating a new data activity Identification (data activity in this, but not in the previous frame) and thus switches the counter reading for new data further by "one" and if this counter reading does not exceed the value 46, then the AND gate 55 leaves the corresponding "one" designation after the corresponding new mask position by.

So if the new data counter overflows while the new data counter has no overflow in its If the counter reading is increased, the counter reading for new activity is reset to 46 and the corresponding one Bit position of a virtual channel in the new mask is set to "one" so that the corresponding a real channel is assigned to the virtual channel. But this has new data activity over a telephone activity for the allocation of a real channel takes precedence.

Activity identifier indicating a continued activity (both in the current framework and in the previous Frame) are selected by an AND gate 56 and switch the count for continued Activity continues and via an AND element 57 to transmit a "one" to the corresponding bit position the corresponding mask for continued activity, provided that this count does not have the value of 46 exceeds. If this count exceeds the value 46, the AND gate 57 is blocked and the count is reset after a corresponding delay. If, however, even if the AND element 57 is blocked, the associated virtual channel is assigned data, then the AND element 50 becomes unconditional unlocked so that the corresponding bit position of the mask is set to "1". So thus has continued data activity Take precedence over continued telephone activity. Continued telephone activity can be countered

over new telephone activity by setting the overflow threshold of the payer for new activity below 46. It is well known that in the Telephony technology, the telephony transmission consists of individual conversation segments. The oppression of a virtual channel containing new voice activity effectively suppresses that in the present system first 6 milliseconds of such a beginning language. In the next frame, however, the activity status of the suppressed virtual channel changes again to continued activity. Therefore, if one prioritizes continued activity over new telephone activity, then normally only the first 6 milliseconds of new voice transmission will be through the Voice occupancy compression suppressed. As is generally known, such a suppression does not affect the intelligibility at the receiving end.

The signaling with respect to the satellite is shown in Figs. 14 to 16 shown. The duration of each satellite frame is 6 microseconds (Fig. 16) and 56 consecutive frames form a main frame a duration of 336 milliseconds (Fig. 14). A fixed section in each frame is used to transmit a bundle of signaling segments or Assigned to control segments that are transmitted from a connected station for monitoring and control purposes. The rest of the main frame is assigned to the individual speech or information transmission bundles of different duration. All of these information transmission bundles are timed so that they arrive nested with one another without overlapping at the satellite (Fig. IS).

The signaling segment bundles of consecutive frames of a main frame become more consecutive. Assigned to earthfoot nodes. Consequently uses a kth in the kth frame of a main frame Station transmit the signaling segment bundle with the corresponding time channel for the transmission of its monitoring and control signals and in the rest of this frame the stations to which corresponding traffic bundle time segments are assigned, their traffic bundles of different durations.

If a switching request is transmitted between the stations within a main frame via the signaling segment channels, then this information is processed in the corresponding network access unit in order to make corresponding extrapolated requests to determine the satellite frame and over a period of 9 main frames, which together form a large frame form, the information transmitted via the signaling segment channels is exchanged, which is evaluated by the network access unit, which then re-assigns its assigned traffic bundle time segments for each frame and thereby compensates for the utilization of the satellite link.

The signaling segment format for connected stations (stations that are already fully synchronized in the network and use the satellite at least for the transmission of monitoring signals with respect to the opposite stations) is shown in the top line of FIG. 16 shown. The signaling segment format of unoccupied stations or stations that are currently unoccupied need to set up a connection to another station is specified in the next line. Both Signaling segment formats are used to transmit information relating to the recovery of the clock frequency of word information and for control information. The one used to recover the clock frequency Information is used by the outgoing and other stations for bit synchronization with the subsequent information. The control words are used for Timing the station that goes up first

S sends, d. H. for differential Doppler tracking of the Satellites. The control information transmitted for unoccupied or newly requesting stations is only used the distinction between the signaling segments and the signaling segments that have already been switched through and satellite tracking stations. The control information segment of an already connected station is used for the assignment of a call request, connection of the remote connection and others Monitoring signals. Signaling segments through

IS switched stations also contain the identification of the station and information regarding the range of the satellite.

The bursts of traffic transmitted by each station in each frame contain bit time (bit clock) recovery information. those through the destination stations is used, as well as control word information (control word no. 3), through which the transmitted information bundles can be recognized as traffic bundles. The different duration of the other traffic bundles includes the kehr itself, the SBK mask information from a different number of network control units 10. in accordance with a previous request prediction, as well as a time assignment of the current one Bundle of information. The abbreviation MZE or multiple Access unit represents the share of traffic that the corresponding network access unit 12 is derived from the up to 4 network control units 10 via connecting trunk lines 10.1. Each such multiple access unit contains the voice reservation compression mask.

provided by the original network control unit 10 with respect to the originating trunk line 10.1 followed by the corresponding channels with voice occupancy compression in their traffic volume subjected traffic. The ones in the pipelines EKU incoming monitoring information is taken from the network access units 12 and, if this information is to be transmitted over the satellite transmission link (e.g. for connecting long distance calls), then this information is in the for transmit the control information provided section of a signaling segment bundle.

Since the 6 millisecond pulse frames of the satellite match the 6 millisecond pulse frames of the Connecting trunk lines will coincide in each

so satellite frames obviously have a large number of frames coming from the connecting trunk lines Transmit traffic in addition to the signaling segment bundle. It can thus be seen that the network access units 12 for the incoming trunk lines Concentrate the traffic considerably more in terms of time.

FIG. 17 shows how network switching boundary conditions can be changed by an externally intervening network management 100. The network management 100 can communicate with a data transmission terminal 102 of one of the network control units 10 and with the common processor 34 via normal land lines be connected to this unit. The connection to the processor 34 thus gives access to segmented availability availability tables of this unit. The network connection lines, including the satellite link. make it the network management 100 possible with all units 10, 12, 14 and 16 of the corresponding

ΊΒ "

17th

Connect to the network. The network access units 12 are initially programmed by locally arranged turntables to process a corresponding traffic request and the assignment of the time interval provided for traffic bundles cuts (requirement assignment) is processed with respect to the satellite. The network control units 10 are programmed (e.g. via a connection to the network management 100) so that a highly effective use of the satellite transmission and also a balanced and gradually expandable utilization of the connecting long-distance lines 10.1, 5 and 5.1 results.

The network management 100 normally only receives information via the line connection 102 processes this information for administrative functions or for billing purposes. The recorded Information also contains a measure for the voice occupancy compression per network control unit performed blocking of virtual channels by means of logic circuits, not shown, in which the Number of suppressions of activity bits when generating the voice allocation compression mask in the circuit of FIG. 3 is counted. The recorded information also gives an indication of network failures. If this is indicated, a failed input means that it can be isolated from the network by sending corresponding information to the network management 100 (via the various connecting and main network lines) is transmitted to the other units, so that connection restrictions can be felt for parts of a traffic connection with the isolated unit is effectively prevented. Furthermore can, if necessary, bring his repentant unit into the system thereby introduced without difficulty or interruption of the operation of the system that of the N'erzvterkmanagemenf ICO relevant information is passed on to the other units via the network's line system.

At the network control units 10 at the other end of the overall network, information output by the network management 100 is output in virtual channels provided for data transmission to output line connections 104, which are switched through to the processor 34 immediately after the corresponding common control unit. The other possibility, namely the use of the channels EKO serving for the monitoring signal transmission and the channels serving for the transmission of the signaling segments, would be less effective, since the latter channels can be very heavily loaded and the joint control with the processor 34 would have the additional task of hide network management traffic from the composite monitoring tool.

In addition 8 sheets of drawings

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Claims (1)

Patent claims: 1. Gradually expandable telephone and data switching device for the optionally switchable connection setup between a number of relatively independent telephone and data connections via time-division multiplex channels of remote connection lines, via multiplex intermediate stations with multiple nodes and several sub-networks connected to the nodes via trunk lines, in a satellite communication system with time division multiple access (TDMA) and time allocation voice interpolation (JTASI), as well as with a switching unit for time slot allocation and intermediate storage of the transmitted information, characterized in that modularly arranged network control units (10) are provided which have a Nptawerk access unit (12) are concentrated, and that each network control unit provides (Fig. 3):